/*
 * Copyright 2021 HIMSA II K/S - www.himsa.com.
 * Represented by EHIMA - www.ehima.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <base/bind.h>
#include <base/callback.h>
#include <base/logging.h>
#include <base/strings/string_number_conversions.h>
#include <hardware/bt_csis.h>
#include <hardware/bt_gatt_types.h>

#include <list>
#include <string>
#include <vector>

#include "advertise_data_parser.h"
#include "bta_api.h"
#include "bta_csis_api.h"
#include "bta_gatt_api.h"
#include "bta_gatt_queue.h"
#include "bta_groups.h"
#include "btif_storage.h"
#include "csis_types.h"
#include "gap_api.h"
#include "gatt_api.h"
#include "osi/include/osi.h"
#include "osi/include/properties.h"
#include "stack/btm/btm_dev.h"
#include "stack/btm/btm_int.h"
#include "stack/btm/btm_sec.h"
#include "stack/crypto_toolbox/crypto_toolbox.h"

using base::Closure;
using bluetooth::Uuid;
using bluetooth::csis::ConnectionState;
using bluetooth::csis::CsisClient;
using bluetooth::csis::CsisDevice;
using bluetooth::csis::CsisDiscoveryState;
using bluetooth::csis::CsisGroup;
using bluetooth::csis::CsisGroupLockStatus;
using bluetooth::csis::CsisInstance;
using bluetooth::csis::CsisLockCb;
using bluetooth::csis::CsisLockState;
using bluetooth::csis::kCsisLockUuid;
using bluetooth::csis::kCsisRankUuid;
using bluetooth::csis::kCsisServiceUuid;
using bluetooth::csis::kCsisSirkUuid;
using bluetooth::csis::kCsisSizeUuid;

using bluetooth::groups::DeviceGroups;
using bluetooth::groups::DeviceGroupsCallbacks;

namespace {
class CsisClientImpl;
CsisClientImpl* instance;
DeviceGroupsCallbacks* device_group_callbacks;

/**
 * -----------------------------------------------------------------------------
 * Coordinated Set Service - Client role
 * -----------------------------------------------------------------------------
 *
 * CSIP allows to organize audio servers into sets e.g. Stereo Set, 5.1 Set
 * and speed up connecting it.
 *
 * Since leaudio has already grouping API it was decided to integrate here CSIS
 * and allow it to group devices semi-automatically.
 *
 * Flow:
 * If connected device contains CSIS services, and it is included into CAP
 * service or is not included at all, implementation reads all its
 * characteristisc. The only mandatory characteristic is Set Identity Resolving
 * Key (SIRK) and once this is read implementation assumes there is at least 2
 * devices in the set and start to search for other members by looking for new
 * Advertising Type (RSI Type) and Resolvable Set Identifier (RSI) in it.
 * In the meantime other CSIS characteristics are read and Set Size might be
 * updated. When new set member is found, there is callback called to upper
 * layer with the address and group id for which member has been found. During
 * this time Search is stopped. Upper layers bonds new devices and connect Le
 * Audio profile. If there are other members to find, implementations repeats
 * the procedure.
 *
 */

class CsisClientImpl : public CsisClient {
  static constexpr uint8_t CSIS_STORAGE_CURRENT_LAYOUT_MAGIC = 0x10;
  static constexpr size_t CSIS_STORAGE_HEADER_SZ =
      sizeof(CSIS_STORAGE_CURRENT_LAYOUT_MAGIC) +
      sizeof(uint8_t); /* num_of_sets */
  static constexpr size_t CSIS_STORAGE_ENTRY_SZ =
      sizeof(uint8_t) /* set_id */ + sizeof(uint8_t) /* desired_size */ +
      Octet16().size();

 public:
  CsisClientImpl(bluetooth::csis::CsisClientCallbacks* callbacks,
                 Closure initCb)
      : gatt_if_(0), callbacks_(callbacks) {
    BTA_GATTC_AppRegister(
        [](tBTA_GATTC_EVT event, tBTA_GATTC* p_data) {
          if (instance && p_data) instance->GattcCallback(event, p_data);
        },
        base::Bind(
            [](Closure initCb, uint8_t client_id, uint8_t status) {
              if (status != GATT_SUCCESS) {
                LOG(ERROR) << "Can't start Coordinated Set Service client "
                              "profile - no gatt clients left!";
                return;
              }
              instance->gatt_if_ = client_id;
              initCb.Run();

              DeviceGroups::Initialize(device_group_callbacks);
              instance->dev_groups_ = DeviceGroups::Get();
            },
            initCb),
        true);

    DLOG(INFO) << __func__ << " Background scan enabled";
    CsisObserverSetBackground(true);
  }

  ~CsisClientImpl() override = default;

  std::shared_ptr<bluetooth::csis::CsisGroup> AssignCsisGroup(
      const RawAddress& address, int group_id,
      bool create_group_if_non_existing, const bluetooth::Uuid& uuid) {
    auto csis_group = FindCsisGroup(group_id);
    if (!csis_group) {
      if (create_group_if_non_existing) {
        /* Let's create a group */
        auto g = std::make_shared<CsisGroup>(group_id, uuid);
        csis_groups_.push_back(g);
        csis_group = FindCsisGroup(group_id);
      } else {
        LOG(ERROR) << __func__ << ": Missing group - that shall not happen";
        return nullptr;
      }
    }

    auto device = FindDeviceByAddress(address);
    if (device == nullptr) {
      auto dev = std::make_shared<CsisDevice>(address, false);
      devices_.push_back(dev);
      device = FindDeviceByAddress(address);
    }

    if (!csis_group->IsDeviceInTheGroup(device)) csis_group->AddDevice(device);

    return csis_group;
  }

  void OnGroupAddedCb(const RawAddress& address, const bluetooth::Uuid& uuid,
                      int group_id) {
    DLOG(INFO) << __func__ << " address: " << address << " uuid: " << uuid
               << " group_id: " << group_id;

    AssignCsisGroup(address, group_id, true, uuid);
  }

  void OnGroupMemberAddedCb(const RawAddress& address, int group_id) {
    DLOG(INFO) << __func__ << " address: " << address
               << " group_id: " << group_id;

    AssignCsisGroup(address, group_id, false, Uuid::kEmpty);
  }

  void OnGroupRemovedCb(const bluetooth::Uuid& uuid, int group_id) {
    RemoveCsisGroup(group_id);
  }

  void OnGroupMemberRemovedCb(const RawAddress& address, int group_id) {
    DLOG(INFO) << __func__ << ": " << address << " group_id: " << group_id;

    auto device = FindDeviceByAddress(address);
    if (device) RemoveCsisDevice(device, group_id);
  }

  void OnGroupAddFromStorageCb(const RawAddress& address,
                               const bluetooth::Uuid& uuid, int group_id) {
    auto device = FindDeviceByAddress(address);
    if (device == nullptr) return;

    auto csis_group = FindCsisGroup(group_id);
    if (csis_group == nullptr) {
      LOG(ERROR) << __func__ << "the csis group (id: " << group_id
                 << ") does not exist";
      return;
    }

    if (!csis_group->IsDeviceInTheGroup(device)) {
      LOG(ERROR) << __func__ << "the csis group (id: " << group_id
                 << ") does contain the device: " << address;
      return;
    }

    if (csis_group->GetUuid() == Uuid::kEmpty) {
      csis_group->SetUuid(uuid);
    }

    callbacks_->OnDeviceAvailable(device->addr, csis_group->GetGroupId(),
                                  csis_group->GetDesiredSize(), uuid);
  }

  void Connect(const RawAddress& address) override {
    DLOG(INFO) << __func__ << ": " << address;

    auto device = FindDeviceByAddress(address);
    if (device == nullptr) {
      devices_.emplace_back(std::make_shared<CsisDevice>(address, true));
    } else {
      device->connecting_actively = true;
    }

    BTA_GATTC_Open(gatt_if_, address, true, false);
  }

  void Disconnect(const RawAddress& addr) override {
    DLOG(INFO) << __func__ << ": " << addr;

    btif_storage_set_csis_autoconnect(addr, false);

    auto device = FindDeviceByAddress(addr);
    if (device == nullptr) {
      LOG(WARNING) << "Device not connected to profile" << addr;
      return;
    }

    /* Removes all active connections or registrations for connection */
    if (device->IsConnected()) {
      BTA_GATTC_Close(device->conn_id);
    } else {
      BTA_GATTC_CancelOpen(gatt_if_, addr, false);
      DoDisconnectCleanUp(device);
    }
  }

  void RemoveDevice(const RawAddress& addr) override {
    DLOG(INFO) << __func__ << ": " << addr;

    auto device = FindDeviceByAddress(addr);
    if (!device) return;

    Disconnect(addr);

    dev_groups_->RemoveDevice(addr);
    btif_storage_remove_csis_device(addr);
  }

  int GetGroupId(const RawAddress& addr, Uuid uuid) override {
    auto device = FindDeviceByAddress(addr);
    if (device == nullptr) return bluetooth::groups::kGroupUnknown;

    int group_id = dev_groups_->GetGroupId(addr, uuid);
    auto csis_group = FindCsisGroup(group_id);
    if (csis_group == nullptr) return bluetooth::groups::kGroupUnknown;

    return csis_group->GetGroupId();
  }

  void HandleCsisLockProcedureError(
      std::shared_ptr<CsisGroup>& csis_group,
      std::shared_ptr<CsisDevice>& csis_device,
      CsisGroupLockStatus status =
          CsisGroupLockStatus::FAILED_LOCKED_BY_OTHER) {
    /* Clear information about ongoing lock procedure */
    CsisLockCb cb = csis_group->GetLockCb();
    csis_group->SetTargetLockState(CsisLockState::CSIS_STATE_UNSET);

    int group_id = csis_group->GetGroupId();
    CsisLockState current_lock_state = csis_group->GetCurrentLockState();
    /* Send unlock to previous devices. It shall be done in reverse order. */
    auto prev_dev = csis_group->GetPrevDevice(csis_device);
    while (prev_dev) {
      if (prev_dev->IsConnected()) {
        auto prev_csis_instance = prev_dev->GetCsisInstanceByGroupId(group_id);
        LOG_ASSERT(prev_csis_instance) << " prev_csis_instance does not exist!";
        SetLock(prev_dev, prev_csis_instance, current_lock_state);
      }
      prev_dev = csis_group->GetPrevDevice(prev_dev);
    }
    /* Call application callback */
    NotifyGroupStatus(group_id, false, status, std::move(cb));
  }

  void OnGattCsisWriteLockRsp(uint16_t conn_id, tGATT_STATUS status,
                              uint16_t handle, void* data) {
    auto device = FindDeviceByConnId(conn_id);
    if (device == nullptr) {
      LOG(ERROR) << __func__ << " Device not there";
      return;
    }

    int group_id = PTR_TO_UINT(data);
    auto csis_group = FindCsisGroup(group_id);
    if (csis_group == nullptr) {
      LOG(ERROR) << __func__ << " There is no group? " << group_id;
      return;
    }

    CsisLockState target_lock_state = csis_group->GetTargetLockState();
    if (target_lock_state == CsisLockState::CSIS_STATE_UNSET) return;

    if (status != GATT_SUCCESS &&
        status != bluetooth::csis::kCsisErrorCodeLockAlreadyGranted) {
      if (target_lock_state == CsisLockState::CSIS_STATE_UNLOCKED) {
        /* When unlocking just drop the counter on error and that is it */
        csis_group->UpdateLockTransitionCnt(-1);
        return;
      }

      /* In case of GATT ERROR */
      LOG(ERROR) << __func__ << " Incorrect write status "
                 << loghex((int)(status));

      /* Unlock previous devices */
      HandleCsisLockProcedureError(csis_group, device);
      return;
    }

    /* All is good, continue. Try to send lock to other devices.*/
    auto csis_instance = device->GetCsisInstanceByGroupId(group_id);
    LOG_ASSERT(csis_instance) << " csis_instance does not exist!";
    csis_instance->SetLockState(target_lock_state);

    if (csis_group->GetLockTransitionCnt() == 0) {
      LOG(ERROR) << __func__ << " Not expected lock state";
      return;
    }

    if (csis_group->UpdateLockTransitionCnt(-1) == 0) {
      csis_group->SetCurrentLockState(csis_group->GetTargetLockState());
      CsisLockCompleted(
          csis_group,
          csis_group->GetCurrentLockState() == CsisLockState::CSIS_STATE_LOCKED,
          CsisGroupLockStatus::SUCCESS);
      return;
    }

    if (target_lock_state == CsisLockState::CSIS_STATE_LOCKED) {
      std::shared_ptr<CsisDevice> next_dev;

      do {
        next_dev = csis_group->GetNextDevice(device);
        if (!next_dev) break;
      } while (!next_dev->IsConnected());

      if (next_dev) {
        auto next_csis_inst = next_dev->GetCsisInstanceByGroupId(group_id);
        LOG_ASSERT(csis_instance) << " csis_instance does not exist!";
        if (next_csis_inst->GetLockState() ==
            CsisLockState::CSIS_STATE_LOCKED) {
          /* Somebody else managed to lock it.
           * Unlock previous devices
           */
          HandleCsisLockProcedureError(csis_group, device);
          return;
        }
        SetLock(next_dev, next_csis_inst, CsisLockState::CSIS_STATE_LOCKED);
      }
    }
  }

  void SetLock(std::shared_ptr<CsisDevice>& device,
               std::shared_ptr<CsisInstance>& csis_instance,
               CsisLockState lock) {
    std::vector<uint8_t> value = {
        (std::underlying_type<CsisLockState>::type)lock};

    LOG(INFO) << __func__ << " " << device->addr
              << " rank: " << int(csis_instance->GetRank()) << " conn_id "
              << device->conn_id << " handle "
              << loghex(+(csis_instance->svc_data.lock_handle.val_hdl));

    BtaGattQueue::WriteCharacteristic(
        device->conn_id, csis_instance->svc_data.lock_handle.val_hdl, value,
        GATT_WRITE,
        [](uint16_t conn_id, tGATT_STATUS status, uint16_t handle, uint16_t len,
           const uint8_t* value, void* data) {
          if (instance)
            instance->OnGattCsisWriteLockRsp(conn_id, status, handle, data);
        },
        UINT_TO_PTR(csis_instance->GetGroupId()));
  }

  void NotifyGroupStatus(int group_id, bool lock, CsisGroupLockStatus status,
                         CsisLockCb cb) {
    callbacks_->OnGroupLockChanged(group_id, lock, status);
    if (cb) std::move(cb).Run(group_id, lock, status);
  }

  std::vector<RawAddress> GetDeviceList(int group_id) override {
    std::vector<RawAddress> result;
    auto csis_group = FindCsisGroup(group_id);

    if (!csis_group || csis_group->IsEmpty()) return result;

    auto csis_device = csis_group->GetFirstDevice();
    while (csis_device) {
      result.push_back(csis_device->addr);
      csis_device = csis_group->GetNextDevice(csis_device);
    }

    return result;
  }

  void LockGroup(int group_id, bool lock, CsisLockCb cb) override {
    if (lock)
      DLOG(INFO) << __func__ << " Locking group: " << int(group_id);
    else
      DLOG(INFO) << __func__ << " Unlocking group: " << int(group_id);

    /* For now we try to lock only connected devices in the group
     * TODO: We can consider reconnected to not connected devices and then
     * locked them
     */
    auto csis_group = FindCsisGroup(group_id);
    if (csis_group == nullptr) {
      LOG(ERROR) << __func__ << " Group not found: " << group_id;
      NotifyGroupStatus(group_id, false,
                        CsisGroupLockStatus::FAILED_INVALID_GROUP,
                        std::move(cb));
      return;
    }

    if (csis_group->IsEmpty()) {
      NotifyGroupStatus(group_id, false,
                        CsisGroupLockStatus::FAILED_GROUP_EMPTY, std::move(cb));
      return;
    }

    if (csis_group->GetTargetLockState() != CsisLockState::CSIS_STATE_UNSET) {
      /* CSIS operation ongoing */

      DLOG(INFO) << __func__ << " Lock operation ongoing:"
                 << "group id: " << group_id << "target state "
                 << (csis_group->GetTargetLockState() ==
                             CsisLockState::CSIS_STATE_LOCKED
                         ? "lock"
                         : "unlock");
      return;
    }

    CsisLockState new_lock_state = lock ? CsisLockState::CSIS_STATE_LOCKED
                                        : CsisLockState::CSIS_STATE_UNLOCKED;

    if (csis_group->GetCurrentLockState() == new_lock_state) {
      DLOG(INFO) << __func__ << " Nothing to do as requested lock is there";
      NotifyGroupStatus(group_id, lock, CsisGroupLockStatus::SUCCESS,
                        std::move(cb));
      return;
    }

    if (lock && !csis_group->IsAvailableForCsisLockOperation()) {
      DLOG(INFO) << __func__ << " Group " << group_id << " locked by other";
      NotifyGroupStatus(group_id, false,
                        CsisGroupLockStatus::FAILED_LOCKED_BY_OTHER,
                        std::move(cb));
      return;
    }

    csis_group->SetTargetLockState(new_lock_state, std::move(cb));

    if (lock) {
      /* In locking case we need to make sure we lock all the device
       * and that in case of error on the way to lock the group, we
       * can revert lock previously locked devices as per specification.
       */
      auto csis_device = csis_group->GetFirstDevice();
      auto csis_instance = csis_device->GetCsisInstanceByGroupId(group_id);
      LOG_ASSERT(csis_instance) << " csis_instance does not exist!";
      SetLock(csis_device, csis_instance, new_lock_state);
    } else {
      /* For unlocking, we don't have to monitor status of unlocking device,
       * therefore, we can just send unlock to all of them, in oposite rank
       * order and check if we get new state notification.
       */
      auto csis_device = csis_group->GetLastDevice();
      auto csis_instance = csis_device->GetCsisInstanceByGroupId(group_id);
      LOG_ASSERT(csis_instance) << " csis_instance does not exist!";
      while (csis_device) {
        if ((csis_device->IsConnected()) &&
            ((csis_instance->GetLockState() != new_lock_state))) {
          csis_group->UpdateLockTransitionCnt(1);
          SetLock(csis_device, csis_instance, new_lock_state);
        }
        csis_device = csis_group->GetPrevDevice(csis_device);
      }
    }
  }

  bool SerializeSets(const RawAddress& addr, std::vector<uint8_t>& out) const {
    auto device = FindDeviceByAddress(addr);
    if (device == nullptr) {
      LOG(WARNING) << __func__ << " Skipping unknown device addr= " << addr;
      return false;
    }

    if (device->GetNumberOfCsisInstances() == 0) {
      LOG(WARNING) << __func__ << " No CSIS instances for addr= " << addr;
      return false;
    }

    DLOG(INFO) << __func__ << ": device=" << device->addr;

    auto num_sets = device->GetNumberOfCsisInstances();
    if ((num_sets == 0) || (num_sets > std::numeric_limits<uint8_t>::max()))
      return false;

    out.resize(CSIS_STORAGE_HEADER_SZ + (num_sets * CSIS_STORAGE_ENTRY_SZ));
    auto* ptr = out.data();

    /* header */
    UINT8_TO_STREAM(ptr, CSIS_STORAGE_CURRENT_LAYOUT_MAGIC);
    UINT8_TO_STREAM(ptr, num_sets);

    /* set entries */
    device->ForEachCsisInstance(
        [&](const std::shared_ptr<CsisInstance>& csis_inst) {
          auto gid = csis_inst->GetGroupId();
          auto csis_group = FindCsisGroup(gid);
          if (csis_group == nullptr) {
            LOG(ERROR) << "SerializeSets: No matching group found!";
            return;
          }

          UINT8_TO_STREAM(ptr, gid);
          UINT8_TO_STREAM(ptr, csis_group->GetDesiredSize());
          Octet16 sirk = csis_group->GetSirk();
          memcpy(ptr, sirk.data(), sirk.size());
          ptr += sirk.size();
        });

    return true;
  }

  void DeserializeSets(const RawAddress& addr, const std::vector<uint8_t>& in) {
    if (in.size() < CSIS_STORAGE_HEADER_SZ + CSIS_STORAGE_ENTRY_SZ) return;
    auto* ptr = in.data();

    uint8_t magic;
    STREAM_TO_UINT8(magic, ptr);

    if (magic == CSIS_STORAGE_CURRENT_LAYOUT_MAGIC) {
      uint8_t num_sets;
      STREAM_TO_UINT8(num_sets, ptr);

      if (in.size() <
          CSIS_STORAGE_HEADER_SZ + (num_sets * CSIS_STORAGE_ENTRY_SZ)) {
        LOG(ERROR) << "Invalid persistent storage data";
        return;
      }

      /* sets entries */
      while (num_sets--) {
        uint8_t gid;
        Octet16 sirk;
        uint8_t size;

        STREAM_TO_UINT8(gid, ptr);
        STREAM_TO_UINT8(size, ptr);
        STREAM_TO_ARRAY(sirk.data(), ptr, (int)sirk.size());

        // Set grouping and SIRK
        auto csis_group = AssignCsisGroup(addr, gid, true, Uuid::kEmpty);
        csis_group->SetDesiredSize(size);
        csis_group->SetSirk(sirk);
      }
    }
  }

  void AddFromStorage(const RawAddress& addr, const std::vector<uint8_t>& in,
                      bool autoconnect) {
    DeserializeSets(addr, in);

    auto device = FindDeviceByAddress(addr);
    if (device == nullptr) {
      device = std::make_shared<CsisDevice>(addr, false);
      devices_.push_back(device);
    }

    for (const auto& csis_group : csis_groups_) {
      if (!csis_group->IsDeviceInTheGroup(device)) continue;

      if (csis_group->GetUuid() != Uuid::kEmpty) {
        callbacks_->OnDeviceAvailable(device->addr, csis_group->GetGroupId(),
                                      csis_group->GetDesiredSize(),
                                      csis_group->GetUuid());
      }
    }

    if (autoconnect) {
      BTA_GATTC_Open(gatt_if_, addr, false, false);
    }
  }

  void CleanUp() {
    DLOG(INFO) << __func__;

    BTA_GATTC_AppDeregister(gatt_if_);
    for (auto& device : devices_) {
      if (device->IsConnected()) BTA_GATTC_Close(device->conn_id);
      DoDisconnectCleanUp(device);
    }

    devices_.clear();

    CsisObserverSetBackground(false);
    dev_groups_->CleanUp(device_group_callbacks);
  }

  void Dump(int fd) {
    std::stringstream stream;

    stream << "  Groups\n";
    for (const auto& g : csis_groups_) {
      stream << "    == id: " << g->GetGroupId() << " ==\n"
             << "    uuid: " << g->GetUuid() << "\n"
             << "    desired size: " << g->GetDesiredSize() << "\n"
             << "    discoverable state: "
             << static_cast<int>(g->GetDiscoveryState()) << "\n"
             << "    current lock state: "
             << static_cast<int>(g->GetCurrentLockState()) << "\n"
             << "    target lock state: "
             << static_cast<int>(g->GetTargetLockState()) << "\n"
             << "    devices: \n";
      for (auto& device : devices_) {
        if (!g->IsDeviceInTheGroup(device)) continue;

        stream << "        == addr: " << device->addr << " ==\n"
               << "        csis instance: data:"
               << "\n";

        auto instance = device->GetCsisInstanceByGroupId(g->GetGroupId());
        if (!instance) {
          stream << "          No csis instance available\n";
        } else {
          stream << "          rank: " << instance->GetRank() << "\n";
        }

        if (!device->IsConnected()) {
          stream << "        Not connected\n";
        } else {
          stream << "        Connected conn_id = "
                 << std::to_string(device->conn_id) << "\n";
        }
      }
    }

    dprintf(fd, "%s", stream.str().c_str());
  }

 private:
  std::shared_ptr<CsisDevice> FindDeviceByConnId(uint16_t conn_id) {
    auto it = find_if(devices_.begin(), devices_.end(),
                      CsisDevice::MatchConnId(conn_id));
    if (it != devices_.end()) return (*it);

    return nullptr;
  }

  void RemoveCsisDevice(std::shared_ptr<CsisDevice>& device, int group_id) {
    auto it = find_if(devices_.begin(), devices_.end(),
                      CsisDevice::MatchAddress(device->addr));
    if (it == devices_.end()) return;

    if (group_id != bluetooth::groups::kGroupUnknown) {
      auto csis_group = FindCsisGroup(group_id);
      if (!csis_group) {
        /* This could happen when remove device is called when bonding is
         * removed */
        DLOG(INFO) << __func__ << " group not found " << group_id;
        return;
      }

      csis_group->RemoveDevice(device->addr);
      if (csis_group->IsEmpty()) {
        RemoveCsisGroup(group_id);
      }
      device->RemoveCsisInstance(group_id);
    }

    if (device->GetNumberOfCsisInstances() == 0) {
      devices_.erase(it);
    }
  }

  std::shared_ptr<CsisDevice> FindDeviceByAddress(
      const RawAddress& addr) const {
    auto it = find_if(devices_.cbegin(), devices_.cend(),
                      CsisDevice::MatchAddress(addr));
    if (it != devices_.end()) return (*it);

    return nullptr;
  }

  std::shared_ptr<CsisGroup> FindCsisGroup(int group_id) const {
    auto it =
        find_if(csis_groups_.cbegin(), csis_groups_.cend(),
                [group_id](auto& g) { return (group_id == g->GetGroupId()); });

    if (it == csis_groups_.end()) return nullptr;
    return (*it);
  }

  void RemoveCsisGroup(int group_id) {
    for (auto it = csis_groups_.begin(); it != csis_groups_.end(); it++) {
      if ((*it)->GetGroupId() == group_id) {
        csis_groups_.erase(it);
        return;
      }
    }
  }

  /* Handle encryption */
  void OnEncrypted(std::shared_ptr<CsisDevice>& device) {
    DLOG(INFO) << __func__ << " " << device->addr;

    if (device->is_gatt_service_valid) {
      NotifyCsisDeviceValidAndStoreIfNeeded(device);
    } else {
      BTA_GATTC_ServiceSearchRequest(device->conn_id, &kCsisServiceUuid);
    }
  }

  void NotifyCsisDeviceValidAndStoreIfNeeded(
      std::shared_ptr<CsisDevice>& device) {
    /* Notify that we are ready to go. Notice that multiple callback calls
     * for a single device address can be called if device is in more than one
     * CSIS group.
     */
    bool notify_connected = false;
    for (const auto& csis_group : csis_groups_) {
      if (!csis_group->IsDeviceInTheGroup(device)) continue;

      int group_id = csis_group->GetGroupId();
      auto csis_instance = device->GetCsisInstanceByGroupId(group_id);
      DLOG(INFO) << __func__ << " group id " << group_id;

      if (!csis_instance) {
        /* This can happen when some other user added device to group in the
         * context which is not existing on the peer side. e.g. LeAudio added it
         * in the CAP context, but CSIS exist on the peer device without a
         * context. We will endup in having device in 2 groups. One in generic
         * context with valid csis_instance, and one in CAP context without csis
         * instance */
        LOG(INFO) << __func__ << " csis_instance does not exist for group "
                  << group_id;
        continue;
      }

      callbacks_->OnDeviceAvailable(device->addr, group_id,
                                    csis_group->GetDesiredSize(),
                                    csis_instance->GetUuid());
      notify_connected = true;
    }
    if (notify_connected)
      callbacks_->OnConnectionState(device->addr, ConnectionState::CONNECTED);

    if (device->first_connection) {
      device->first_connection = false;
      btif_storage_set_csis_autoconnect(device->addr, true);
    }
  }

  void OnGattWriteCcc(uint16_t conn_id, tGATT_STATUS status, uint16_t handle,
                      void* user_data) {
    LOG(INFO) << __func__ << " handle=" << loghex(handle);

    auto device = FindDeviceByConnId(conn_id);
    if (device == nullptr) {
      LOG(INFO) << __func__ << " unknown conn_id=" << loghex(conn_id);
      BtaGattQueue::Clean(conn_id);
      return;
    }
  }

  void OnCsisNotification(uint16_t conn_id, uint16_t handle, uint16_t len,
                          const uint8_t* value) {
    auto device = FindDeviceByConnId(conn_id);
    if (device == nullptr) {
      LOG(WARNING) << "Skipping unknown device, conn_id=" << loghex(conn_id);
      return;
    }

    auto csis_instance = device->GetCsisInstanceByOwningHandle(handle);
    if (csis_instance == nullptr) {
      LOG(ERROR) << __func__
                 << " unknown notification handle: " << loghex(handle)
                 << " for conn_id: " << loghex(conn_id);
      return;
    }

    if (handle == csis_instance->svc_data.sirk_handle.val_hdl) {
      OnCsisSirkValueUpdate(conn_id, GATT_SUCCESS, handle, len, value);
    } else if (handle == csis_instance->svc_data.lock_handle.val_hdl) {
      OnCsisLockNotifications(device, csis_instance, len, value);
    } else if (handle == csis_instance->svc_data.size_handle.val_hdl) {
      OnCsisSizeValueUpdate(conn_id, GATT_SUCCESS, handle, len, value);
    } else {
      LOG(WARNING) << __func__ << " unknown notification handle "
                   << loghex(handle) << " for conn_id " << loghex(conn_id);
    }
  }

  static CsisGroupLockStatus LockError2GroupLockStatus(tGATT_STATUS status) {
    switch (status) {
      case bluetooth::csis::kCsisErrorCodeLockDenied:
        return CsisGroupLockStatus::FAILED_LOCKED_BY_OTHER;
      case bluetooth::csis::kCsisErrorCodeReleaseNotAllowed:
        return CsisGroupLockStatus::FAILED_LOCKED_BY_OTHER;
      case bluetooth::csis::kCsisErrorCodeInvalidValue:
        return CsisGroupLockStatus::FAILED_OTHER_REASON;
      default:
        return CsisGroupLockStatus::FAILED_OTHER_REASON;
    }
  }

  void CsisLockCompleted(std::shared_ptr<CsisGroup>& csis_group, bool lock,
                         CsisGroupLockStatus status) {
    DLOG(INFO) << __func__ << " group id: " << int(csis_group->GetGroupId())
               << "target state " << (lock ? "lock" : "unlock");

    NotifyGroupStatus(csis_group->GetGroupId(), lock, status,
                      std::move(csis_group->GetLockCb()));
    csis_group->SetTargetLockState(CsisLockState::CSIS_STATE_UNSET);
  }

  void OnCsisLockNotifications(std::shared_ptr<CsisDevice>& device,
                               std::shared_ptr<CsisInstance>& csis_instance,
                               uint16_t len, const uint8_t* value) {
    if (len != 1) {
      LOG(ERROR) << __func__ << " invalid notification len: " << loghex(len);
      return;
    }

    CsisLockState new_lock = (CsisLockState)(value[0]);

    DLOG(INFO) << " New lock state: " << int(new_lock)
               << " device rank:  " << int(csis_instance->GetRank()) << "\n";

    csis_instance->SetLockState(new_lock);

    auto csis_group = FindCsisGroup(csis_instance->GetGroupId());
    if (!csis_group) return;

    CsisLockCb cb = csis_group->GetLockCb();
    if (csis_group->GetTargetLockState() == CsisLockState::CSIS_STATE_UNSET) {
      if (csis_group->GetCurrentLockState() ==
              CsisLockState::CSIS_STATE_LOCKED &&
          new_lock == CsisLockState::CSIS_STATE_UNLOCKED) {
        /* We are here when members fires theirs lock timeout.
         * Not sure what to do with our current lock state. For now we will
         * change local lock state after first set member removes its lock. Then
         * we count that others will do the same
         */
        csis_group->SetCurrentLockState(CsisLockState::CSIS_STATE_UNLOCKED);
        NotifyGroupStatus(csis_group->GetGroupId(), false,
                          CsisGroupLockStatus::SUCCESS, std::move(cb));
      }
      return;
    }

    if (csis_group->GetCurrentLockState() != csis_group->GetTargetLockState()) {
      /* We are in process of changing lock state. If new device lock
       * state is what is targeted that means all is good, we don't need
       * to do here nothing, as state will be changed once all the
       * characteristics are written. If new device state is not what is
       * targeted, that means, device changed stated unexpectedly and locking
       * procedure is broken
       */
      if (new_lock != csis_group->GetTargetLockState()) {
        /* Device changed back the lock state from what we expected, skip
         * locking and notify user about that
         */
        CsisLockCompleted(csis_group, false,
                          CsisGroupLockStatus::FAILED_OTHER_REASON);
      }
    }
  }

  void OnCsisSizeValueUpdate(uint16_t conn_id, tGATT_STATUS status,
                             uint16_t handle, uint16_t len,
                             const uint8_t* value) {
    auto device = FindDeviceByConnId(conn_id);

    if (device == nullptr) {
      LOG(WARNING) << "Skipping unknown device, conn_id=" << loghex(conn_id);
      return;
    }

    DLOG(INFO) << __func__ << " " << device->addr
               << " status: " << loghex(+status);

    if (status != GATT_SUCCESS) {
      LOG(ERROR) << __func__ << " Could not read characteristic at handle="
                 << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    if (len != 1) {
      LOG(ERROR) << "Invalid size value length=" << +len
                 << " at handle=" << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    auto csis_instance = device->GetCsisInstanceByOwningHandle(handle);
    if (csis_instance == nullptr) {
      LOG(ERROR) << __func__ << " Unknown csis instance";
      BTA_GATTC_Close(device->conn_id);
      return;
    }
    auto csis_group = FindCsisGroup(csis_instance->GetGroupId());
    if (!csis_group) {
      LOG(ERROR) << __func__ << " Unknown group id yet";
      return;
    }

    csis_group->SetDesiredSize(value[0]);
  }

  void OnCsisLockReadRsp(uint16_t conn_id, tGATT_STATUS status, uint16_t handle,
                         uint16_t len, const uint8_t* value) {
    auto device = FindDeviceByConnId(conn_id);
    if (device == nullptr) {
      LOG(WARNING) << "Skipping unknown device, conn_id=" << loghex(conn_id);
      return;
    }

    LOG(INFO) << __func__ << " " << device->addr
              << " status: " << loghex(+status);

    if (status != GATT_SUCCESS) {
      LOG(ERROR) << __func__ << " Could not read characteristic at handle="
                 << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    if (len != 1) {
      LOG(ERROR) << " Invalid lock value length=" << +len
                 << " at handle=" << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    auto csis_instance = device->GetCsisInstanceByOwningHandle(handle);
    if (csis_instance == nullptr) {
      LOG(ERROR) << __func__ << " Unknown csis instance";
      BTA_GATTC_Close(device->conn_id);
      return;
    }
    csis_instance->SetLockState((CsisLockState)(value[0]));
  }

  void OnCsisRankReadRsp(uint16_t conn_id, tGATT_STATUS status, uint16_t handle,
                         uint16_t len, const uint8_t* value) {
    auto device = FindDeviceByConnId(conn_id);
    if (device == nullptr) {
      LOG(WARNING) << __func__
                   << " Skipping unknown device, conn_id=" << loghex(conn_id);
      return;
    }

    DLOG(INFO) << __func__ << " " << device->addr
               << " status: " << loghex(+status) << " rank:" << int(value[0]);

    if (status != GATT_SUCCESS) {
      LOG(ERROR) << __func__ << " Could not read characteristic at handle="
                 << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    if (len != 1) {
      LOG(ERROR) << __func__ << "Invalid rank value length=" << +len
                 << " at handle=" << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    auto csis_instance = device->GetCsisInstanceByOwningHandle(handle);
    if (csis_instance == nullptr) {
      LOG(ERROR) << __func__ << " Unknown csis instance handle " << int(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    csis_instance->SetRank((value[0]));
    auto csis_group = FindCsisGroup(csis_instance->GetGroupId());
    csis_group->SortByCsisRank();
  }

  void OnCsisObserveCompleted(void) {
    if (discovering_group_ == -1) {
      LOG(ERROR) << __func__ << " No ongoing CSIS discovery - disable scan";
      return;
    }

    auto csis_group = FindCsisGroup(discovering_group_);
    discovering_group_ = -1;
    if (csis_group->IsGroupComplete())
      csis_group->SetDiscoveryState(
          CsisDiscoveryState::CSIS_DISCOVERY_COMPLETED);
    else
      csis_group->SetDiscoveryState(CsisDiscoveryState::CSIS_DISCOVERY_IDLE);

    LOG(INFO) << __func__;
  }

  /*
   * Sirk shall be in LE order
   * encrypted_sirk: LE order
   */
  bool sdf(const RawAddress& address, const Octet16& encrypted_sirk,
           Octet16& sirk) {
    tBTM_SEC_DEV_REC* p_dev_rec = btm_find_dev(address);
    if (!p_dev_rec) {
      LOG(ERROR) << __func__ << " No security for " << address;
      return false;
    }

    DLOG(INFO) << __func__ << " LTK "
               << base::HexEncode(p_dev_rec->ble.keys.pltk.data(), 16);
    DLOG(INFO) << __func__ << " IRK "
               << base::HexEncode(p_dev_rec->ble.keys.irk.data(), 16);

    /* Calculate salt CSIS d1.0r05 4.3 */
    Octet16 zero_key;
    memset(zero_key.data(), 0, 16);

    std::string msg1 = "SIRKenc";
    std::reverse(msg1.begin(), msg1.end());

    Octet16 s1 = crypto_toolbox::aes_cmac(zero_key, (uint8_t*)(msg1.c_str()),
                                          msg1.size());
    DLOG(INFO) << "s1 (le) " << base::HexEncode(s1.data(), 16);

    /* Create K = LTK */
    DLOG(INFO) << "K (le) "
               << base::HexEncode(p_dev_rec->ble.keys.pltk.data(), 16) << "\n";

    Octet16 T = crypto_toolbox::aes_cmac(s1, p_dev_rec->ble.keys.pltk);
    DLOG(INFO) << "T (le)" << base::HexEncode(T.data(), 16) << "\n";

    std::string msg2 = "csis";
    std::reverse(msg2.begin(), msg2.end());

    Octet16 k1 =
        crypto_toolbox::aes_cmac(T, (uint8_t*)(msg2.c_str()), msg2.size());
    DLOG(INFO) << "K1 (le) " << base::HexEncode(k1.data(), 16) << "\n";

    for (int i = 0; i < 16; i++) sirk[i] = encrypted_sirk[i] ^ k1[i];

    DLOG(INFO) << "SIRK (le)" << base::HexEncode(sirk.data(), 16) << "\n";
    return true;
  }

  std::vector<RawAddress> GetAllRsiFromAdvertising(
      const tBTA_DM_INQ_RES* result) {
    const uint8_t* p_service_data = result->p_eir;
    uint16_t remaining_data_len = result->eir_len;
    std::vector<RawAddress> devices;
    uint8_t service_data_len = 0;

    while ((p_service_data = AdvertiseDataParser::GetFieldByType(
                p_service_data + service_data_len,
                (remaining_data_len -= service_data_len), BTM_BLE_AD_TYPE_RSI,
                &service_data_len))) {
      RawAddress bda;
      STREAM_TO_BDADDR(bda, p_service_data);
      devices.push_back(std::move(bda));
    }

    return std::move(devices);
  }

  void OnActiveScanResult(const tBTA_DM_INQ_RES* result) {
    auto csis_device = FindDeviceByAddress(result->bd_addr);
    if (csis_device) {
      DLOG(INFO) << __func__ << " Drop same device .." << result->bd_addr;
      return;
    }

    auto all_rsi = GetAllRsiFromAdvertising(result);
    if (all_rsi.empty()) return;

    /* Notify only the actively searched group */
    auto csis_group = FindCsisGroup(discovering_group_);
    if (csis_group == nullptr) {
      LOG(ERROR) << " No ongoing CSIS discovery - disable scan";
      CsisActiveObserverSet(false);
      return;
    }

    auto discovered_group_rsi = std::find_if(
        all_rsi.cbegin(), all_rsi.cend(), [&csis_group](const auto& rsi) {
          return csis_group->IsRsiMatching(rsi);
        });
    if (discovered_group_rsi != all_rsi.cend()) {
      DLOG(INFO) << "Found set member " << result->bd_addr;
      callbacks_->OnSetMemberAvailable(result->bd_addr,
                                       csis_group->GetGroupId());

      /* Switch back to the opportunistic observer mode.
       * When second device will pair, csis will restart active scan
       * to search more members if needed */
      CsisActiveObserverSet(false);
      csis_group->SetDiscoveryState(CsisDiscoveryState::CSIS_DISCOVERY_IDLE);
    }
  }

  void CsisActiveObserverSet(bool enable) {
    LOG(INFO) << __func__ << " CSIS Discovery SET: " << enable;

    BTA_DmBleCsisObserve(
        enable, [](tBTA_DM_SEARCH_EVT event, tBTA_DM_SEARCH* p_data) {
          /* If there's no instance we are most likely shutting
           * down the whole stack and we can ignore this event.
           */
          if (instance == nullptr) return;

          if (event == BTA_DM_INQ_CMPL_EVT) {
            LOG(INFO) << "BLE observe complete. Num Resp: "
                      << static_cast<int>(p_data->inq_cmpl.num_resps);
            instance->OnCsisObserveCompleted();
            instance->CsisObserverSetBackground(true);
            return;
          }

          if (event != BTA_DM_INQ_RES_EVT) {
            LOG(WARNING) << "Unknown event: " << event;
            return;
          }

          instance->OnActiveScanResult(&p_data->inq_res);
        });
    BTA_DmBleScan(enable, bluetooth::csis::kDefaultScanDurationS);

    /* Need to call it by ourselfs */
    if (!enable) {
      OnCsisObserveCompleted();
      CsisObserverSetBackground(true);
    }
  }

  void CsisActiveDiscovery(std::shared_ptr<CsisGroup> csis_group) {
    if ((csis_group->GetDiscoveryState() !=
         CsisDiscoveryState::CSIS_DISCOVERY_IDLE)) {
      LOG(ERROR) << __func__
                 << " Incorrect ase group: " << csis_group->GetGroupId()
                 << " state "
                 << loghex(static_cast<int>(csis_group->GetDiscoveryState()));
      return;
    }

    csis_group->SetDiscoveryState(CsisDiscoveryState::CSIS_DISCOVERY_ONGOING);
    /* TODO Maybe we don't need it */
    discovering_group_ = csis_group->GetGroupId();
    CsisActiveObserverSet(true);
  }

  void OnScanBackgroundResult(const tBTA_DM_INQ_RES* result) {
    if (csis_groups_.empty()) return;

    auto csis_device = FindDeviceByAddress(result->bd_addr);
    if (csis_device) {
      DLOG(INFO) << __func__ << " Drop same device .." << result->bd_addr;
      return;
    }

    auto all_rsi = GetAllRsiFromAdvertising(result);
    if (all_rsi.empty()) return;

    /* Notify all the groups this device belongs to. */
    for (auto& group : csis_groups_) {
      for (auto& rsi : all_rsi) {
        if (group->IsRsiMatching(rsi)) {
          DLOG(INFO) << " Found set member in background scan "
                     << result->bd_addr;
          callbacks_->OnSetMemberAvailable(result->bd_addr,
                                           group->GetGroupId());
          break;
        }
      }
    }
  }

  void CsisObserverSetBackground(bool enable) {
    DLOG(INFO) << __func__ << " CSIS Discovery background: " << enable;

    BTA_DmBleCsisObserve(
        enable, [](tBTA_DM_SEARCH_EVT event, tBTA_DM_SEARCH* p_data) {
          /* If there's no instance we are most likely shutting
           * down the whole stack and we can ignore this event.
           */
          if (instance == nullptr) return;

          if (event == BTA_DM_INQ_CMPL_EVT) {
            DLOG(INFO) << "BLE observe complete. Num Resp: "
                       << static_cast<int>(p_data->inq_cmpl.num_resps);
            return;
          }

          if (event != BTA_DM_INQ_RES_EVT) {
            LOG(WARNING) << "Unknown event: " << event;
            return;
          }

          instance->OnScanBackgroundResult(&p_data->inq_res);
        });
  }

  void OnCsisSirkValueUpdate(uint16_t conn_id, tGATT_STATUS status,
                             uint16_t handle, uint16_t len,
                             const uint8_t* value,
                             bool notify_valid_services = true) {
    auto device = FindDeviceByConnId(conn_id);
    if (device == nullptr) {
      LOG(WARNING) << __func__
                   << " Skipping unknown device, conn_id=" << loghex(conn_id);
      return;
    }

    DLOG(INFO) << __func__ << " " << device->addr
               << " status: " << loghex(+status);

    if (status != GATT_SUCCESS) {
      /* TODO handle error codes:
       * kCsisErrorCodeLockAccessSirkRejected
       * kCsisErrorCodeLockOobSirkOnly
       */
      LOG(ERROR) << __func__ << " Could not read characteristic at handle="
                 << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    if (len != bluetooth::csis::kCsisSirkCharLen) {
      LOG(ERROR) << "Invalid sirk value length=" << +len
                 << " at handle=" << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    auto csis_instance = device->GetCsisInstanceByOwningHandle(handle);
    if (csis_instance == nullptr) {
      LOG(ERROR) << __func__ << " Unknown csis instance: handle "
                 << loghex(handle);
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    uint8_t sirk_type = value[0];
    LOG(INFO) << __func__ << " SIRK Type: " << +sirk_type;

    /* Verify if sirk is not all zeros */
    Octet16 zero{};
    if (memcmp(zero.data(), value + 1, 16) == 0) {
      LOG(ERROR) << "Received invalid zero SIRK address: "
                 << loghex(device->conn_id) << ". Disconnecting ";
      BTA_GATTC_Close(device->conn_id);
      return;
    }

    Octet16 received_sirk;
    memcpy(received_sirk.data(), value + 1, 16);

    if (sirk_type == bluetooth::csis::kCsisSirkTypeEncrypted) {
      /* Decrypt encrypted SIRK */
      Octet16 sirk;
      sdf(device->addr, received_sirk, sirk);
      received_sirk = sirk;
    }

    /* SIRK is ready. Add device to the group */

    std::shared_ptr<CsisGroup> csis_group;
    int group_id = csis_instance->GetGroupId();
    if (group_id != bluetooth::groups::kGroupUnknown) {
      /* Group already exist. */
      csis_group = FindCsisGroup(group_id);
      LOG_ASSERT(csis_group) << " group does not exist? " << group_id;
    } else {
      /* Now having SIRK we can decide if the device belongs to some group we
       * know or this is a new group
       */
      for (auto& g : csis_groups_) {
        if (g->IsSirkBelongsToGroup(received_sirk)) {
          group_id = g->GetGroupId();
          break;
        }
      }

      if (group_id == bluetooth::groups::kGroupUnknown) {
        /* Here it means, we have new group. Let's us create it */
        group_id =
            dev_groups_->AddDevice(device->addr, csis_instance->GetUuid());
        LOG_ASSERT(group_id != -1);

        /* Create new group */
        auto g =
            std::make_shared<CsisGroup>(group_id, csis_instance->GetUuid());
        csis_groups_.push_back(g);
      } else {
        dev_groups_->AddDevice(device->addr, csis_instance->GetUuid(),
                               group_id);
      }

      csis_group = FindCsisGroup(group_id);
      csis_group->AddDevice(device);
      /* Let's update csis instance group id */
      csis_instance->SetGroupId(group_id);
    }

    csis_group->SetSirk(received_sirk);
    device->is_gatt_service_valid = true;
    btif_storage_update_csis_info(device->addr);

    if (notify_valid_services) NotifyCsisDeviceValidAndStoreIfNeeded(device);

    DLOG(INFO) << " SIRK " << base::HexEncode(received_sirk.data(), 16)
               << " address" << device->addr;

    DLOG(INFO) << " Expected group size "
               << loghex(csis_group->GetDesiredSize())
               << ", actual group Size: "
               << loghex(csis_group->GetCurrentSize());

    /* Start active search for the other device */
    if (csis_group->GetDesiredSize() > csis_group->GetCurrentSize())
      CsisActiveDiscovery(csis_group);
  }

  void DoDisconnectCleanUp(std::shared_ptr<CsisDevice> device) {
    DLOG(INFO) << __func__ << ": device=" << device->addr;

    device->ForEachCsisInstance(
        [&](const std::shared_ptr<CsisInstance>& csis_inst) {
          DisableGattNotification(device->conn_id, device->addr,
                                  csis_inst->svc_data.lock_handle.val_hdl);
          DisableGattNotification(device->conn_id, device->addr,
                                  csis_inst->svc_data.sirk_handle.val_hdl);
          DisableGattNotification(device->conn_id, device->addr,
                                  csis_inst->svc_data.size_handle.val_hdl);
        });

    if (device->IsConnected()) {
      BtaGattQueue::Clean(device->conn_id);
      device->conn_id = GATT_INVALID_CONN_ID;
    }
  }

  bool OnCsisServiceFound(std::shared_ptr<CsisDevice> device,
                          const gatt::Service* service,
                          const bluetooth::Uuid& context_uuid,
                          bool is_last_instance) {
    DLOG(INFO) << __func__ << " service handle: " << loghex(service->handle)
               << " end handle: " << loghex(service->end_handle)
               << " uuid: " << context_uuid;

    auto csis_inst = std::make_shared<CsisInstance>(
        (uint16_t)service->handle, (uint16_t)service->end_handle, context_uuid);

    /* Let's check if we know group of this device */
    int group_id = dev_groups_->GetGroupId(device->addr, context_uuid);
    if (group_id != bluetooth::groups::kGroupUnknown)
      csis_inst->SetGroupId(group_id);

    /* Initially validate and store GATT service discovery data */
    for (const gatt::Characteristic& charac : service->characteristics) {
      if (charac.uuid == kCsisLockUuid) {
        /* Find the mandatory CCC descriptor */
        uint16_t ccc_handle =
            FindCccHandle(device->conn_id, charac.value_handle);
        if (ccc_handle == GAP_INVALID_HANDLE) {
          DLOG(ERROR) << __func__
                      << ": no HAS Active Preset CCC descriptor found!";
          return false;
        }
        csis_inst->svc_data.lock_handle.val_hdl = charac.value_handle;
        csis_inst->svc_data.lock_handle.ccc_hdl = ccc_handle;

        SubscribeForNotifications(device->conn_id, device->addr,
                                  charac.value_handle, ccc_handle);

        DLOG(INFO) << __func__ << " Lock UUID found handle: "
                   << loghex(csis_inst->svc_data.lock_handle.val_hdl)
                   << " ccc handle: "
                   << loghex(csis_inst->svc_data.lock_handle.ccc_hdl);
      } else if (charac.uuid == kCsisRankUuid) {
        csis_inst->svc_data.rank_handle = charac.value_handle;

        DLOG(INFO) << __func__ << " Rank UUID found handle: "
                   << loghex(csis_inst->svc_data.rank_handle);
      } else if (charac.uuid == kCsisSirkUuid) {
        /* Find the optional CCC descriptor */
        uint16_t ccc_handle =
            FindCccHandle(device->conn_id, charac.value_handle);
        csis_inst->svc_data.sirk_handle.ccc_hdl = ccc_handle;
        csis_inst->svc_data.sirk_handle.val_hdl = charac.value_handle;

        if (ccc_handle != GAP_INVALID_HANDLE)
          SubscribeForNotifications(device->conn_id, device->addr,
                                    charac.value_handle, ccc_handle);

        DLOG(INFO) << __func__ << " SIRK UUID found handle: "
                   << loghex(csis_inst->svc_data.sirk_handle.val_hdl)
                   << " ccc handle: "
                   << loghex(csis_inst->svc_data.sirk_handle.ccc_hdl);
      } else if (charac.uuid == kCsisSizeUuid) {
        /* Find the optional CCC descriptor */
        uint16_t ccc_handle =
            FindCccHandle(device->conn_id, charac.value_handle);
        csis_inst->svc_data.size_handle.ccc_hdl = ccc_handle;
        csis_inst->svc_data.size_handle.val_hdl = charac.value_handle;

        if (ccc_handle != GAP_INVALID_HANDLE)
          SubscribeForNotifications(device->conn_id, device->addr,
                                    charac.value_handle, ccc_handle);

        DLOG(INFO) << __func__ << " Size UUID found handle: "
                   << loghex(csis_inst->svc_data.size_handle.val_hdl)
                   << " ccc handle: "
                   << loghex(csis_inst->svc_data.size_handle.ccc_hdl);
      }
    }

    /* Sirk is the only mandatory characteristic. If it is in
     * place, service is OK
     */
    if (csis_inst->svc_data.sirk_handle.val_hdl == GAP_INVALID_HANDLE) {
      /* We have some characteristics but all dependencies are not satisfied */
      LOG(ERROR) << __func__ << " Service has a broken structure.";
      return false;
    }
    device->SetCsisInstance(csis_inst->svc_data.start_handle, csis_inst);

    /* Read SIRK */
    BtaGattQueue::ReadCharacteristic(
        device->conn_id, csis_inst->svc_data.sirk_handle.val_hdl,
        [](uint16_t conn_id, tGATT_STATUS status, uint16_t handle, uint16_t len,
           uint8_t* value, void* user_data) {
          if (instance)
            instance->OnCsisSirkValueUpdate(conn_id, status, handle, len, value,
                                            (bool)user_data);
        },
        (void*)is_last_instance);

    /* Read Lock */
    if (csis_inst->svc_data.lock_handle.val_hdl != GAP_INVALID_HANDLE) {
      BtaGattQueue::ReadCharacteristic(
          device->conn_id, csis_inst->svc_data.lock_handle.val_hdl,
          [](uint16_t conn_id, tGATT_STATUS status, uint16_t handle,
             uint16_t len, uint8_t* value, void* user_data) {
            if (instance)
              instance->OnCsisLockReadRsp(conn_id, status, handle, len, value);
          },
          nullptr);
    }

    /* Read Size */
    if (csis_inst->svc_data.size_handle.val_hdl != GAP_INVALID_HANDLE) {
      BtaGattQueue::ReadCharacteristic(
          device->conn_id, csis_inst->svc_data.size_handle.val_hdl,
          [](uint16_t conn_id, tGATT_STATUS status, uint16_t handle,
             uint16_t len, uint8_t* value, void* user_data) {
            if (instance)
              instance->OnCsisSizeValueUpdate(conn_id, status, handle, len,
                                              value);
          },
          nullptr);
    }

    /* Read Rank */
    if (csis_inst->svc_data.rank_handle != GAP_INVALID_HANDLE) {
      BtaGattQueue::ReadCharacteristic(
          device->conn_id, csis_inst->svc_data.rank_handle,
          [](uint16_t conn_id, tGATT_STATUS status, uint16_t handle,
             uint16_t len, uint8_t* value, void* user_data) {
            if (instance)
              instance->OnCsisRankReadRsp(conn_id, status, handle, len, value);
          },
          nullptr);
    }
    return true;
  }

  /* These are all generic GATT event handlers calling HAS specific code. */
  void GattcCallback(tBTA_GATTC_EVT event, tBTA_GATTC* p_data) {
    LOG(INFO) << __func__ << " event = " << static_cast<int>(event);

    /* This is in case Csis CleanUp is already done
     * while GATT is still up and could send events
     */
    if (!instance) return;

    switch (event) {
      case BTA_GATTC_DEREG_EVT:
        break;

      case BTA_GATTC_OPEN_EVT:
        OnGattConnected(p_data->open);
        break;

      case BTA_GATTC_CLOSE_EVT:
        OnGattDisconnected(p_data->close);
        break;

      case BTA_GATTC_SEARCH_CMPL_EVT:
        OnGattServiceSearchComplete(p_data->search_cmpl);
        break;

      case BTA_GATTC_NOTIF_EVT:
        OnGattNotification(p_data->notify);
        break;

      case BTA_GATTC_ENC_CMPL_CB_EVT:
        OnLeEncryptionComplete(p_data->enc_cmpl.remote_bda, BTM_SUCCESS);
        break;

      case BTA_GATTC_SRVC_CHG_EVT:
        OnGattServiceChangeEvent(p_data->remote_bda);
        break;

      case BTA_GATTC_SRVC_DISC_DONE_EVT:
        OnGattServiceDiscoveryDoneEvent(p_data->remote_bda);
        break;

      default:
        break;
    }
  }

  void OnGattConnected(const tBTA_GATTC_OPEN& evt) {
    DLOG(INFO) << __func__ << ": address=" << evt.remote_bda
               << ", conn_id=" << evt.conn_id;

    auto device = FindDeviceByAddress(evt.remote_bda);
    if (device == nullptr) {
      DLOG(WARNING) << "Skipping unknown device, address=" << evt.remote_bda;
      BTA_GATTC_Close(evt.conn_id);
      return;
    }

    if (evt.status != GATT_SUCCESS) {
      DLOG(INFO) << "Failed to connect to server device";
      if (device->connecting_actively)
        callbacks_->OnConnectionState(evt.remote_bda,
                                      ConnectionState::DISCONNECTED);
      DoDisconnectCleanUp(device);
      return;
    }

    device->connecting_actively = false;
    device->conn_id = evt.conn_id;

    /* Verify bond */
    uint8_t sec_flag = 0;
    BTM_GetSecurityFlagsByTransport(evt.remote_bda, &sec_flag, BT_TRANSPORT_LE);

    /* If link has been encrypted look for the service or report */
    if (sec_flag & BTM_SEC_FLAG_ENCRYPTED) {
      if (device->is_gatt_service_valid) {
        instance->OnEncrypted(device);
      } else {
        BTA_GATTC_ServiceSearchRequest(device->conn_id, &kCsisServiceUuid);
      }

      return;
    }

    int result = BTM_SetEncryption(
        evt.remote_bda, BT_TRANSPORT_LE,
        [](const RawAddress* bd_addr, tBT_TRANSPORT transport, void* p_ref_data,
           tBTM_STATUS status) {
          if (instance) instance->OnLeEncryptionComplete(*bd_addr, status);
        },
        nullptr, BTM_BLE_SEC_ENCRYPT);

    DLOG(INFO) << __func__
               << " Encryption required. Request result: " << result;
  }

  void OnGattDisconnected(const tBTA_GATTC_CLOSE& evt) {
    auto device = FindDeviceByAddress(evt.remote_bda);
    if (device == nullptr) {
      LOG(WARNING) << "Skipping unknown device disconnect, conn_id="
                   << loghex(evt.conn_id);
      return;
    }

    DLOG(INFO) << __func__ << ": device=" << device->addr;

    callbacks_->OnConnectionState(evt.remote_bda,
                                  ConnectionState::DISCONNECTED);

    // Unlock others only if device was locked by us but has disconnected
    // unexpectedly.
    if ((evt.reason == GATT_CONN_TIMEOUT) ||
        (evt.reason == GATT_CONN_TERMINATE_PEER_USER)) {
      device->ForEachCsisInstance(
          [&](const std::shared_ptr<CsisInstance>& csis_inst) {
            auto csis_group = FindCsisGroup(csis_inst->GetGroupId());
            if (csis_group == nullptr) return;
            if ((csis_group->GetCurrentLockState() ==
                 CsisLockState::CSIS_STATE_LOCKED)) {
              HandleCsisLockProcedureError(
                  csis_group, device,
                  CsisGroupLockStatus::LOCKED_GROUP_MEMBER_LOST);
            }
          });
    }

    DoDisconnectCleanUp(device);
  }

  void OnGattServiceSearchComplete(const tBTA_GATTC_SEARCH_CMPL& evt) {
    auto device = FindDeviceByConnId(evt.conn_id);

    if (device == nullptr) {
      LOG(WARNING) << __func__ << " Skipping unknown device, conn_id="
                   << loghex(evt.conn_id);
      return;
    }

    /* Ignore if our service data is valid (discovery initiated by someone
     * else?) */
    if (!device->is_gatt_service_valid) {
      if (evt.status != GATT_SUCCESS) {
        LOG(ERROR) << __func__ << " Service discovery failed";
        BTA_GATTC_Close(device->conn_id);
        DoDisconnectCleanUp(device);
        return;
      }

      DLOG(INFO) << __func__;

      const std::list<gatt::Service>* all_services =
          BTA_GATTC_GetServices(device->conn_id);

      std::vector<uint16_t> all_csis_start_handles;

      /* Le's just find all the CSIS primary services and store the start
       * handles */
      for (auto& svrc : *all_services) {
        if (svrc.uuid == kCsisServiceUuid) {
          all_csis_start_handles.push_back(svrc.handle);
        }
      }

      if (all_csis_start_handles.size() == 0) {
        DLOG(INFO) << __func__ << " No Csis instances found";
        BTA_GATTC_Close(device->conn_id);
        RemoveCsisDevice(device, bluetooth::groups::kGroupUnknown);
        return;
      }

      for (auto& svrc : *all_services) {
        if (svrc.uuid == kCsisServiceUuid) continue;

        /* Try to find context for CSIS instances */
        for (auto& included_srvc : svrc.included_services) {
          if (included_srvc.uuid == kCsisServiceUuid) {
            auto csis_svrc = BTA_GATTC_GetOwningService(
                device->conn_id, included_srvc.start_handle);
            auto iter = std::find(all_csis_start_handles.begin(),
                                  all_csis_start_handles.end(),
                                  included_srvc.start_handle);
            if (iter != all_csis_start_handles.end())
              all_csis_start_handles.erase(iter);
            instance->OnCsisServiceFound(device, csis_svrc, svrc.uuid,
                                         all_csis_start_handles.empty());
          }
        }
      }

      /* Here if CSIS is included, all_csis_start_handles should be empty
       * Otherwise it means, we have some primary CSIS without a context,
       * which means it is for the complete device.
       * As per spec, there can be only one service like this.
       */
      if (all_csis_start_handles.size()) {
        DLOG(INFO) << __func__ << " there is " << all_csis_start_handles.size()
                   << " primary services without a context";
        auto csis_svrc = BTA_GATTC_GetOwningService(device->conn_id,
                                                    all_csis_start_handles[0]);
        instance->OnCsisServiceFound(
            device, csis_svrc, bluetooth::groups::kGenericContextUuid, true);
        all_csis_start_handles.clear();
      }
    } else {
      /* This might be set already if there is no optional attributes to read
       * or write.
       */
      if (evt.status == GATT_SUCCESS) {
        NotifyCsisDeviceValidAndStoreIfNeeded(device);
      }
    }
  }

  void OnGattNotification(const tBTA_GATTC_NOTIFY& evt) {
    /* Reject invalid lengths and indications as they are not supported */
    if (!evt.is_notify || evt.len > GATT_MAX_ATTR_LEN) {
      LOG(ERROR) << __func__ << ": rejected BTA_GATTC_NOTIF_EVT. is_notify = "
                 << evt.is_notify << ", len=" << static_cast<int>(evt.len);
    }

    OnCsisNotification(evt.conn_id, evt.handle, evt.len, evt.value);
  }

  void OnLeEncryptionComplete(const RawAddress& address, uint8_t status) {
    DLOG(INFO) << __func__ << " " << address;
    auto device = FindDeviceByAddress(address);
    if (device == nullptr) {
      LOG(WARNING) << "Skipping unknown device" << address;
      return;
    }

    if (status != BTM_SUCCESS) {
      LOG(ERROR) << "encryption failed"
                 << " status: " << status;

      BTA_GATTC_Close(device->conn_id);
      return;
    }

    if (device->is_gatt_service_valid) {
      instance->OnEncrypted(device);
    } else {
      device->first_connection = true;
      BTA_GATTC_ServiceSearchRequest(device->conn_id, &kCsisServiceUuid);
    }
  }

  void OnGattServiceChangeEvent(const RawAddress& address) {
    auto device = FindDeviceByAddress(address);
    if (!device) {
      LOG(WARNING) << "Skipping unknown device" << address;
      return;
    }

    DLOG(INFO) << __func__ << ": address=" << address;

    /* Invalidate service discovery results */
    BtaGattQueue::Clean(device->conn_id);
    device->first_connection = true;
    device->ClearSvcData();
  }

  void OnGattServiceDiscoveryDoneEvent(const RawAddress& address) {
    auto device = FindDeviceByAddress(address);
    if (!device) {
      LOG(WARNING) << "Skipping unknown device" << address;
      return;
    }

    DLOG(INFO) << __func__ << ": address=" << address;

    if (!device->is_gatt_service_valid)
      BTA_GATTC_ServiceSearchRequest(device->conn_id, &kCsisServiceUuid);
  }

  static uint16_t FindCccHandle(uint16_t conn_id, uint16_t char_handle) {
    const gatt::Characteristic* p_char =
        BTA_GATTC_GetCharacteristic(conn_id, char_handle);
    if (!p_char) {
      LOG(WARNING) << __func__ << ": No such characteristic: " << char_handle;
      return GAP_INVALID_HANDLE;
    }

    for (const gatt::Descriptor& desc : p_char->descriptors) {
      if (desc.uuid == Uuid::From16Bit(GATT_UUID_CHAR_CLIENT_CONFIG))
        return desc.handle;
    }

    return GAP_INVALID_HANDLE;
  }

  void SubscribeForNotifications(uint16_t conn_id, const RawAddress& address,
                                 uint16_t value_handle, uint16_t ccc_handle) {
    if (value_handle != GAP_INVALID_HANDLE) {
      tGATT_STATUS register_status =
          BTA_GATTC_RegisterForNotifications(gatt_if_, address, value_handle);
      DLOG(INFO) << __func__ << ": BTA_GATTC_RegisterForNotifications, status="
                 << loghex(+register_status)
                 << " value=" << loghex(value_handle)
                 << " ccc=" << loghex(ccc_handle);

      if (register_status != GATT_SUCCESS) return;
    }

    std::vector<uint8_t> value(2);
    uint8_t* value_ptr = value.data();
    UINT16_TO_STREAM(value_ptr, GATT_CHAR_CLIENT_CONFIG_NOTIFICATION);
    BtaGattQueue::WriteDescriptor(
        conn_id, ccc_handle, std::move(value), GATT_WRITE,
        [](uint16_t conn_id, tGATT_STATUS status, uint16_t value_handle,
           uint16_t len, const uint8_t* value, void* user_data) {
          if (instance)
            instance->OnGattWriteCcc(conn_id, status, value_handle, user_data);
        },
        nullptr);
  }

  void DisableGattNotification(uint16_t conn_id, const RawAddress& address,
                               uint16_t value_handle) {
    if (value_handle != GAP_INVALID_HANDLE) {
      tGATT_STATUS register_status =
          BTA_GATTC_DeregisterForNotifications(gatt_if_, address, value_handle);
      DLOG(INFO) << __func__ << ": DisableGattNotification, status="
                 << loghex(+register_status)
                 << " value=" << loghex(value_handle);

      if (register_status != GATT_SUCCESS) return;
    }
  }

  uint8_t gatt_if_;
  bluetooth::csis::CsisClientCallbacks* callbacks_;
  std::list<std::shared_ptr<CsisDevice>> devices_;
  std::list<std::shared_ptr<CsisGroup>> csis_groups_;
  DeviceGroups* dev_groups_;
  int discovering_group_ = -1;
};

class DeviceGroupsCallbacksImpl : public DeviceGroupsCallbacks {
 public:
  void OnGroupAdded(const RawAddress& address, const bluetooth::Uuid& uuid,
                    int group_id) override {
    if (instance) instance->OnGroupAddedCb(address, uuid, group_id);
  }

  void OnGroupMemberAdded(const RawAddress& address, int group_id) override {
    if (instance) instance->OnGroupMemberAddedCb(address, group_id);
  }

  void OnGroupRemoved(const bluetooth::Uuid& uuid, int group_id) override {
    if (instance) instance->OnGroupRemovedCb(uuid, group_id);
  }

  void OnGroupMemberRemoved(const RawAddress& address, int group_id) override {
    if (instance) instance->OnGroupMemberRemovedCb(address, group_id);
  }

  void OnGroupAddFromStorage(const RawAddress& address,
                             const bluetooth::Uuid& uuid,
                             int group_id) override {
    if (instance) instance->OnGroupAddFromStorageCb(address, uuid, group_id);
  }
};

class DeviceGroupsCallbacksImpl;
DeviceGroupsCallbacksImpl deviceGroupsCallbacksImpl;

}  // namespace

void CsisClient::Initialize(bluetooth::csis::CsisClientCallbacks* callbacks,
                            Closure initCb) {
  if (instance) {
    LOG(ERROR) << __func__ << ": Already initialized!";
    return;
  }

  device_group_callbacks = &deviceGroupsCallbacksImpl;
  instance = new CsisClientImpl(callbacks, initCb);
}

bool CsisClient::IsCsisClientRunning() { return instance; }

CsisClient* CsisClient::Get(void) {
  CHECK(instance);
  return instance;
}

void CsisClient::AddFromStorage(const RawAddress& addr,
                                const std::vector<uint8_t>& in,
                                bool autoconnect) {
  if (!instance) {
    LOG(ERROR) << __func__ << ": Not initialized yet!";
    return;
  }

  instance->AddFromStorage(addr, in, autoconnect);
}

bool CsisClient::GetForStorage(const RawAddress& addr,
                               std::vector<uint8_t>& out) {
  if (!instance) {
    LOG(ERROR) << __func__ << ": Not initialized yet";
    return false;
  }

  return instance->SerializeSets(addr, out);
}

void CsisClient::CleanUp() {
  CsisClientImpl* ptr = instance;
  instance = nullptr;

  if (ptr) {
    ptr->CleanUp();
    delete ptr;
  }
}

void CsisClient::DebugDump(int fd) {
  dprintf(fd, "Coordinated Set Service Client:\n");
  if (instance) instance->Dump(fd);
  dprintf(fd, "\n");
}